CH₂³⁵Cl³⁷Cl中ν₃与ν₉之间科里奥利耦合的高分辨率红外研究。

High Resolution IR Study of the Coriolis Coupling between nu3 and nu9 in CH2 35 Cl37 Cl.

作者信息

Snels M

机构信息

Istituto per Materiali Speciali, CNR, Zona Industriale di Tito Scalo, Potenza, I-85050, Italy

出版信息

J Mol Spectrosc. 1997 Jun;183(2):224-7. doi: 10.1006/jmsp.1997.7263.

DOI:10.1006/jmsp.1997.7263

PMID:9252291

Abstract

The infrared spectra of the nu3 and nu9 bands of methylene chloride have been recorded both for isotopically pure CH2 35 Cl2 and for a natural mixture with a resolution of 0.0025-0.004 cm-1 (FWHM) in the range 600-800 cm-1 using a Bruker IFS 120 HR Fourier Transform interferometer. The Coriolis coupling between the two CCl2 stretching fundamentals nu3 and nu9 has been investigated for the CH2 35 Cl37 Cl isotopic species. An effective coupling constant xi39 c = 0.1975(2) cm-1 results from a full rotational analysis of a difference spectrum, obtained by subtracting the CH2 35 Cl2 room temperature spectrum from that of the natural mixture. A least-mean-squares fit of the data to Watson's A-reduction Hamiltonian in the Ir representation yields a set of accurate effective rotational and distortion constants up to quartic terms for the excited states of both fundamental bands. The standard deviation of the fit was 0.893 x 10(-3) cm-1 .

摘要

使用布鲁克IFS 120 HR傅里叶变换干涉仪，在600 - 800 cm-1范围内，以0.0025 - 0.004 cm-1（半高宽）的分辨率记录了二氯甲烷ν3和ν9带的红外光谱，该光谱涵盖了同位素纯的CH2 35 Cl2以及天然混合物。对CH2 35 Cl37 Cl同位素物种研究了两个CCl2伸缩基频ν3和ν9之间的科里奥利耦合。通过从天然混合物的光谱中减去CH2 35 Cl2室温光谱得到差光谱，并对其进行全转动分析，得出有效耦合常数ξ39 c = 0.1975(2) cm-1。在Ir表示中，将数据对沃森A简化哈密顿量进行最小二乘拟合，得到了两个基频带激发态直至四次项的一组精确有效转动常数和畸变常数。拟合的标准偏差为0.893×10(-3) cm-1。